This invention relates to an apparatus for covering open containers, and, more particularly, to an apparatus for covering open top truck containers.
Large open top containers are commonly used to transport loose materials such as construction debris or refuse to landfills or other dumping locations. These containers are often transported on a roll-off truck that has the capability to pick up and off-load the container at desired locations. The tops of such containers are typically open to facilitate loading. In many places, laws and regulations require the tops of such containers to be covered before they can be transported on public roadways so that material from the container cannot be blown out of the containers. Even where there are no laws regarding covering a load, it is beneficial for the driver to cover the load in order to reduce the possibility of damage to other property from rocks or other debris that might escape from the container. These containers typically have a rectangular top opening. The size of these containers may vary, with many containers ranging from 16 to 24 feet in length and 4 to 8 feet in height. It is common for any one roll-off truck to carry a number of different sizes of these containers.
Placing a tarp or cover on a container manually is both time-consuming and expensive. The need for a covering apparatus to accommodate various container sizes that would automatically deploy the cover or at least simplify and speed up the covering process became apparent some time ago.
Several inventions have been proposed to address the need to cover open top containers during transport. One approach has been to provide a spring-loaded spool, mounted to the front of the truck, that moves up and down on a pedestal to suit the height of the container. The driver can then pull the cover off of the spool out over the container opening like one would pull a window shade. Although this semi-automatic covering method is better than manual covering, it is still difficult and time consuming, and requires the driver to fasten the end of the cover that was pulled off of the spool to the container. Many of the prior art devices that automate the covering process are similar to the semi-automated process described above, but have a pivoting arm secured to the truck or truck body on each side of the container. These arms pull the end of the cover over the container. Sometimes these arms are spring-loaded to pull the cover toward the rear of the container as the cover is unrolled from the motor-controlled roller at the front of the container. Sometimes the roller at the front of the container is spring-loaded to roll the cover up on it, and the arms are controlled by a hydraulic cylinder or other suitable mechanism to pull the cover over the container. Further, some of the prior art devices have a spring-loaded roller with the cover rolled onto it and attached to the arms, with the other end of the cover attached to the truck just behind the cab. As the arms pivot, the spool of material is pulled from front to back over the top of the container, thereby unspooling the material so that it lies over the open top, effectively covering the container.
One of the greatest challenges in the covering mechanisms is to provide the ability to adapt to various container lengths and heights. Some containers have a rear door that is higher than the container sides that makes covering the container even more challenging. One approach to these challenges is to provide for a telescopic arm pivotally attached to either the container itself or the truck that transports the container. U.S. Pat. No. 4,874,196 to Goldstein et al. discloses a container mounted telescopic arm arrangement. Although the apparatus of Goldstein is specific to the container on which it is mounted, the principle can also be applied to truck mounted covering mechanisms like that shown in U.S. Pat. No. 5,803,528 to Haddad, Jr. One disadvantage of the exclusively telescopic approach is that such sliding motion is generally more expensive to fabricate and more difficult to maintain than a pivoting motion in the harsh environments to which these covering mechanisms are subjected. The telescopic arm concept is shown in U.S. Pat. Nos. 5,238,287 and U.S. Pat. No. 5,340,187 to Haddad, Jr. One embodiment shown in U.S. Pat. No. 5,829,818 to O""Daniel also utilizes a telescopic arm to accommodate variations in container height.
A second approach to accommodating the various container sizes has been to provide an arm composed of two pivotally connected sections. This concept is illustrated in U.S. Pat. No. 5,292,169 to O""Brian. The pivotal connections of O""Brian are an improvement in terms of fabrication cost and maintenance, but, like the sliding arms, have other disadvantages enumerated below.
A disadvantage of both of these types of covering mechanisms is illustrated in FIG. 7 of U.S. Pat. No. 5,829,818 to O""Daniel. When hauling a container that is short from front to rear, this type of covering mechanism may require the end of the arm that supports the spool of covering material to hang over the back of the container when the cover is applied. This presents several problems. Firstly, the end of the arm is unsupported during transport of the container, and all of the shock loads or dynamic loads that occur are applied directly to the base of the arm. Further, this could put large loads on the cover itself, potentially causing premature failure. These loads could be significant and could require over design of the base structure, with its accorded additional weight, and/or a reduced operating life of the mechanism. Further, the end of the arm is exposed to potential damage because it is the rearmost point on the truck when the cover is applied. Also, if this mechanism was used to cover a container with a rear door that is higher than the container, the cover would leave a triangular portion open on both sides of the container where refuse could escape from the container.
Another disadvantage of both the sliding and pivoting types is that two separate motions control the roller position, the rotation of the base arm and either the extension or rotation of the outer arm. This is a substantial problem if the rolled up cover is stored between the truck cab and the container. To deploy the cover, the roller must initially move in a substantially vertical line from its stored position in between the cab of the truck and the top of the front wall of the container as the container is being covered. Often the space in between the cab and the container is small and any deviation from the vertical path may result in damage to the covering mechanism, the cab of the truck, or the container. One partial solution to this problem has been to mount the stored spool of covering material at or above the top of the cab of the truck. However, this mounting position necessitates a tall support structure for the spool of covering material that at least partially obstructs the view through the back window of the cab. The obstruction of the rear cab window is also present in most of the prior art concepts. Additionally, a tall support structure potentially prevents adequate coverage of the front edge of the container when the containers are comparatively shallow.
A further disadvantage of the pivoting type of the prior art is that in covering short containers, with the roller placed on the rearmost top edge of the container, the base arm would stick up considerably above the top of the container, increasing the possibility of damage to the covering apparatus from tree limbs as the container is being transported.
A further disadvantage of the prior art is that, in the stowed position, at least portions of the arms are substantially above the bottom of the container. Thus, as the container is rolled on and off the vehicle, components of the container, such as hinges and latches, which are typically positioned at the maximum width of the container, are more likely to hit and damage the covering mechanism.
Another problem with manual covering of a container, and with certain semi-automatic covering systems is the risk of injury. When items in a container project upward beyond the top of the container, the operator may need to climb up on the container and/or load to cover the container, or ensure that the covering is able to extend over the items projecting upward out of the container. The risk lies not only in climbing up high off the ground, but also in the parts of the load that could cut or injure the operator. In some prior art container covering systems, it is difficult for the cover to get over such projecting loads, particularly the types of container covering systems that extend linearly over the container.
It is an object of the present invention to provide a container covering apparatus that reduces or wholly overcomes some or all of the difficulties inherent in prior known devices. Particular objects and advantages of the invention will be apparent to those skilled in the art, that is, those who are knowledgeable or experienced in this field of technology, in view of the following disclosure of the invention and detailed description of certain preferred embodiments.
The principles of the present invention may be used advantageously to provide a container covering apparatus that can be adapted to cover containers of various sizes, that is simple to operate and reliable.
In accordance with a first aspect, an apparatus for covering an open container of a vehicle includes a pair of arms. Each arm has a first arm member and a second arm member. A first rotatable member is pivotally secured to the first arm member. A second rotatable member is pivotally secured to the first arm member and rigidly secured to the second arm member. A linking member couples the first and second rotatable members to one another. A first actuator is secured to the first arm member, a second actuator is secured to the first rotatable member, and a cover is connected to the second arm members.
In accordance with another aspect, an apparatus for covering an open container of a vehicle includes a pair of arms. Each arm includes a support member having a first end and a second end. A first arm member is pivotally secured at a first end thereof to the support member. A second arm member is pivotally secured at a first end thereof to a second end of the first arm member. A first sprocket is pivotally secured to the first end of the first arm member. A second sprocket is pivotally secured to the second end of the first arm member and rigidly secured to the first end of the second arm member. A continuous chain is wrapped around each of the first and second sprockets. A first actuator is pivotally secured at a first end thereof to the support member and at a second end thereof to the second end of the first arm member. A second actuator is pivotally secured at a first end thereof to the support member and pivotally secured at a second end thereof to the first sprocket. A cover is rolled upon a spool having opposed ends, with each end of the spool supported at a second end of one of the second arm members.
In accordance with yet another aspect, an apparatus for covering an open container of a vehicle includes a pair of arms. Each arm includes a support member. A first arm member is pivotally secured at a first end thereof to the support member. A second arm member is pivotally secured at a first end thereof to a second end of the first arm member. A first rotatable member is pivotally secured to the first end of the first arm member. A second rotatable member is pivotally secured to the second end of the first arm member and pivotally secured to the first end of the second arm member. A linking member couples the first and second rotatable members to one another. A first actuator is pivotally secured at a first end thereof to the support member and at a second end thereof to the second end of the first arm member. A second actuator is pivotally secured at a first end thereof to the support member and pivotally secured at a second end to the first rotatable member. A cover is connected to the second arm members.
In accordance with a further aspect, an apparatus for covering an open container of a vehicle includes a pair of arms, with each arm including a first arm member and a second arm member rotatable greater than 180xc2x0 with respect to the first arm member. A first rotatable member is pivotally secured to a first end of the first arm member. A second rotatable member is pivotally secured to a second end of the first arm member. A linking member couples the first and second rotatable members to one another. A first actuator is connected to the first arm member and a second actuator is connected to the second arm member. A cover is connected to the second arm members.
In accordance with yet a further aspect, a covering device for covering an open top container supported by a truck frame has an arm assembly on each side of the truck. At least one arm assembly includes a pair of articulated arms coupled to a cover such that movement of at least one of the arms moves the cover between a covering position where the cover overlies the container and a stowage position where the container is uncovered. A pair of disks are coupled by a flaccid member, and one of the arms is fixed to one of the disks such that the one arm pivots about the other arm with movement of the flaccid member to move the cover toward the covering position or the stowage position.
In accordance with another aspect, a process for covering an open top container supported by a truck frame includes the steps of providing a pivoted arm assembly on each side of a truck, the arm assemblies being coupled to a spool supporting a cover; supporting the spool at a front end of the container at a position below the open top of the container; actuating the arm assembly such that the spool is lifted substantially along a vertical plane until the spool is lifted above the open top of the container; and actuating the arm assembly once it is above the open top of the container to move the spool to a rear end of the container so that the cover overlies the open top of the container.
In accordance with yet a further aspect, an apparatus for covering an open container of a vehicle includes a pair of arms, with each arm having a first arm member rotatable in a first plane and a second arm member pivotally connected to the first arm member and rotatable in a second plane laterally offset from the first plane. A cover is connected to the second arm members.
In accordance with still a further aspect, an apparatus for covering an open container of a vehicle includes a pair of arms. Each arm includes a first arm member and a second arm member pivotally connected to the first arm member and having a length greater than a length of the first arm member. A cover is connected to the second arm members.
Substantial advantage is achieved by providing a container covering apparatus. In particular, preferred embodiments of the present invention are able to cover a wide variety of container sizes using an apparatus having a simple, low maintenance construction with low profile design and simple positioning control. Preferred embodiments of the present invention allow a cover to be deployed over a load that extends above a top of a container without an operator needing to climb up on top of the container to ensure the cover can get past the obstructions. Further, preferred embodiments of the present invention provide support for the covering apparatus in its non-deployed condition, and the container itself provides support for a spool of the covering apparatus in its non-deployed condition. Additionally, preferred embodiments of the present invention in their non-deployed position sit low on a vehicle, thereby minimizing the risk of damaging the covering apparatus during loading and unloading of the container. These and additional features and advantages of the invention disclosed here will be further understood from the following detailed disclosure of certain preferred embodiments.